Claims
- 1. A method of curing a polymer thick film on a substrate comprising the steps of:
- (1) providing a polymer thick film composition comprising:
- (a) a resin system comprising an admixture of:
- (i) about 4.50 parts to about 12 parts by weight of at least one phenoxy resin; and
- (ii) about 6 parts to about 15.5 parts by weight of at least one blocked isocyanate resin; and
- (b) a conductive material selected from the group consisting of:
- (i) about 50 parts to about 70 parts by weight silver flake; and
- (ii) an admixture of about 15 to about 25 parts by weight graphite and about 3 parts to about 6 parts by weight of carbon black.
- (2) applying said composition to a substrate; and
- (3) thermally curing said composition onto said substrate.
- 2. The method of claim 1 wherein said applying step 2 is a screen-printing operation.
- 3. The method of claim 1 wherein said curing step is carried out at a temperature from about 120.degree. C. to about 150.degree. C. for a period of time from about 90 minutes to about 20 minutes.
- 4. A substrate having a curved conductive polymer thick film coating thereon which comprises a cured admixture of:
- (a) a cured resin system comprising a reaction product of:
- (i) about 4.50 parts to about 12 parts by weight of at least one phenoxy resin; and
- (ii) about 6 parts to about 15.5 parts by weight of at least one blocked isocyanate resin;
- (b) a conductive material selected from the group consisting of:
- (i) about 50 parts to about 70 parts by weight silver flakes; and
- (ii) an admixture of about 15 to about 25 parts by weight graphite and about 3 parts to about 6 parts by weight carbon black.
- 5. The coated substrate of claim 4 wherein said substrate is flexible.
- 6. The coated substrate of claim 5 wherein said substrate is rigid.
Parent Case Info
This is application is a division of application Ser. No. 07/403,235, filed Sep. 5, 1989, now U.S. Pat. No. 5,049,313 which issued on Sep. 17, 1991.
US Referenced Citations (10)
Divisions (1)
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Number |
Date |
Country |
Parent |
403235 |
Sep 1989 |
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